Sofa



FIG. 1 is a front perspective view of a sofa showing my design;

FIG. 2 is a rear perspective view;

FIG. 3 is a top plan view;

FIG. 4 is a front elevational view;

FIG. 5 is a rear elevational view; and

FIG. 6 is a side elevational view thereof;

FIG. 7 is a front perspective view of a sofa showing a second embodimentof my design; and

FIG. 8 is a rear perspective view thereof.

The ornamental design for a sofa, as shown and described.